1. Field of the Invention
The present invention relates to an operation lever apparatus, and more particularly to an operation lever apparatus which comprises an operation lever operative to issue a plurality of instruction signals to other associated devices and arrangements under the state that the operation lever is handled by one hand of an operator.
2. Description of the Related Art
Up until now, there have been proposed a wide variety of conventional operation lever apparatuses each of which comprises a joystick type of operation lever operative to issue a plurality of instruction signals to other associated devices and arrangements, such as a surveillance camera and a game machine, under the state that the operation lever is handled by one hand of an operator.
The conventional operation lever apparatuses of this type have so far been used for a surveillance system which comprises a surveillance camera available for watching a special room. One typical example of the conventional operation lever apparatus is exemplified and shown in FIGS. 12 and 13. The conventional operation lever apparatus 300 thus proposed comprises a housing member 310 having an operation surface 311 and formed with a housing space therein, first and second operation switches 317 and 318 each provided on the operation surface 311 of the housing member 310, a circuit board 320 accommodated in the housing space of the housing member 310, a detecting unit 330 having a reference axis and provided on the circuit board 320, a operation lever 340 having a reference axis and mounted on the retaining member 330.
Each of the first and second operation switches 317 and 318 is movable with respect to the operation surface 311 of the housing member 310 to assume different switching states. The first operation switch 317 is operative to produce a first switch signal indicative of any one of the switching states of the first operation switch 317 and operative to output the first switch signal to the circuit board 320. The second operation switch 318 is operative to produce a second switch signal indicative of any one of the switching states of the second operation switch 318 and operative to output the second switch signal to the circuit board 320.
The operation lever 340 is movable with respect to the detecting unit 330 to assume two different operation positions including a first position in which the reference axis of the operation lever 340 is held in coaxial relationship with the reference axis of the detecting unit 330, and a second position in which the reference axis of the operation lever 340 is tilted with respect to the reference axis of the detecting unit 330. The operation lever 340 is rockable around the reference axis of the operation lever 340. The operation lever 340 is coupled at one end to the detecting unit 330 to ensure that the operation lever 340 is movable to assume the first and second positions of the operation lever 340 and rockable around the reference axis of the operation lever 340 under the state that the operation lever 340 is handled by one hand of an operator.
The detecting unit 330 is operative to detect a tilt direction of the reference axis of the operation lever 340 with respect to the reference axis of the detecting unit 330 to produce a tilt direction signal indicative of the tilt direction of the reference axis of the operation lever 340. The detecting unit 330 is operative to detect a rock direction of the operation lever 340 with respect to the detecting unit 330 to produce a rock direction signal indicative of the rock direction of the operation lever 340. The detecting unit 330 is operative to output the tilt direction signal and the rock direction signal to the circuit board 320.
The circuit board 320 is designed to issue a plurality of instruction signals to the surveillance camera to control various operations of the surveillance camera. The instruction signals are constituted by the first switch signal produced by the first operation switch 317, the second switch signal produced by the second operation switch 318, the tilt direction signal produced by the detecting unit 330, and the rock direction signal produced by the detecting unit 330.
The circuit board 320 is operative to control a zooming operation of the surveillance camera on the basis of the first switch signal produced by the first operation switch 317, a focusing operation of the surveillance camera on the basis of the second switch signal produced by the second operation switch 318, a shooting direction of the surveillance camera on the basis of the tilt direction signal produced by the detecting unit 330, and another kind of operation of the surveillance camera on the basis of the rock direction signal produced by the detecting unit 330.
The conventional operation lever apparatus described in the above, however, encounters such a problem that the conventional operation lever apparatus is decreased in number of the instruction signals under the state that the operation lever apparatus is handled by one hand of an operator, resulting from the fact that the operation lever is limited in number of the movements thereof.